Add json serialization of sets as list

src/aerovaldb/utils/json.py

@@ -1,11 +1,18 @@
 import simplejson  # type: ignore
 
 
+def json_encoder(obj):
+    if isinstance(obj, set):
+        return list(obj)
+
+    TypeError(repr(obj) + " is not JSON serializable")
+
+
 def json_dumps_wrapper(obj, **kwargs) -> str:
     """
     Wrapper which calls simplejson.dumps with the correct options, known to work for objects
     returned by Pyaerocom.
 
     This ensures that nan values are serialized as null to be compliant with the json standard.
     """
-    return simplejson.dumps(obj, ignore_nan=True, **kwargs)
+    return simplejson.dumps(obj, ignore_nan=True, default=json_encoder, **kwargs)

tests/test_aerovaldb.py

@@ -557,3 +557,19 @@ def test_put_report_image(tmpdb):
 
     assert isinstance(blob, bytes)
     assert len(blob) > 0
+
+
+@pytest.mark.parametrize(
+    "dbtype",
+    (
+        pytest.param(
+            "json_files",
+        ),
+        pytest.param(
+            "sqlitedb",
+        ),
+    ),
+)
+def test_serialize_set(tmpdb):
+    with tmpdb as db:
+        db.put_config({"set": {"a", "b", "c"}}, "test", "test")